After his older brother, King Viserys I Targaryen, refused to name him heir, Prince Daemon Targaryen decided to establish his own kingdom. Daemon joined forces with Corlys in trying to wrestle control of the Stepstones from the so-called Three Daughters. While Corlys commanded the fleet, Daemon led an army of sellswords, cutthroats, landless adventurers, and second sons.[1]

In 106 AC, Daemon invaded the Stepstones atop his dragon, Caraxes. Despite inferior numbers, they inflicted a string of defeats on the Triarchy for two years before Daemon slew Craghas Drahar in single combat with his blade, Dark Sister. By 109 AC, Daemon's armies controlled all but two of the Stepstones, and the Sea Snake's fleets had naval supremacy. Daemon chose the title King of the Stepstones and the Narrow Sea and received his crown from Corlys. Daemon's kingdom was supported financially by the Iron Throne.[1]

In 110 AC, however, the Triarchy dispatched a counterattack led by Racallio Ryndoon, supported by newly-acquired Dornish allies. Fighting continued in 111 AC, when King Daemon withdrew to court at King's Landing for six months. Daemon struggled to defend the Stepstones against the Triarchy and their allies from Dorne.[1]

Upon hearing of the death of his estranged wife, Lady Rhea Royce, in 115 AC, Daemon left his seat at Bloodstone in the Stepstones and attempted to claim Runestone in the Vale of Arryn. Although he failed to acquire Rhea's inheritance, Daemon then married Corlys's daughter, Laena Velaryon, and abandoned the Stepstones altogether. Five other men followed him as King of the Narrow Sea before the Triarchy and Dornish alliance ended the sellsword kingdom he had created.[1]